I read through this page. “ls /usr/share/locale” does not exactly list en_US, but it does display en_US.ISO8859-1, en_US.ISO8859-15, and en_US.UTF-8. Running “env LC_ALL=en_US.UTF-8 perl” makes little difference:

This is just a vanilla installation of OpenBSD? I wonder if the following in your CPAN initial setup would point in the right direction-

Quote:

The next option deals with the charset your terminal supports. In
general CPAN is English speaking territory, thus the charset does not
matter much, but some of the aliens out there who upload their
software to CPAN bear names that are outside the ASCII range. If your
terminal supports UTF-8, you say no to the next question, if it
supports ISO-8859-1 (also known as LATIN1) then you say yes, and if it
supports neither nor, your answer does not matter, you will not be
able to read the names of some authors anyway. If you answer no, names
will be output in UTF-8.

The problem is that I was using UXTerm, which sets LC_CTYPE. I now instead do “xterm -en utf8”—well, actually “XTerm*locale: utf8” is in my .Xdefaults, but they’re the same thing. OpenBSD really is a learning experience

For one, there is no UTF-8 support at the OS level on OpenBSD.
There are UTF-8 /usr/share/locale directories which are empty, hence fallback to C, but this prevent error messages.

For the LC_ALL=C fallback, in the LInux days when they were adapting UTF-8, I used to set the environment to it.
Under OpenBSD default ksh, I often type
env LC_ALL=C [command] [arguments] which does nothing but prevent error messages.

You would set those variables in
~/.profile

Usually (other OSes), the system wide setting would happen in /etc/login.conf
but
as assumption is the mother of all f#ck-ups, checked the manpages and found no indication.
Hence, no answer. I cover my back
Also, don't su but sudo and, in the
/etc/sudoers
uncomment (visudo)
#Defaults:%wheel !env_reset
This would be OK for a one-only sysadmin system.

One of the reasons to use Xorg (/usr/X11R6/share/X11/locale) and UTF-8 aware applications.

Btw, you perfectly can save a file (OS file-system level), with UTF-8 characters in it (application level): UTF-8 aware aplications read it perfectly but the CLI will strip some characters. Just be aware that the CLI shells (OS level) will not do the translation.
Note that this also happens when the filenames have extended ASCII you would read differently under Xorg and the CLI if not set to the same locales|xlocales.

Using OpenBSD as a desktop for some years now, I don't know anymore how mendatory a full UTF-8 support from the OS level up would be vs. keeping the OS in full old plain trusted ASCII-7.